Fig 2: Effect of GSK-3 inhibition during 7-day unloading on rpS6 abundance (a) and phosphorylation status of rpS6 (b) and 4E-BP1 (c) in rat soleus muscle. Data are presented as median, interquartile range, minimum and maximum values, expressed as % of control. C, vivarium control group, C + AR, vivarium control rats + daily injections of GSK-3 inhibitor (AR-A014418) for 7 days, 7HS, hindlimb suspension for 7 days, 7HS + AR, 7-day hindlimb suspension + daily injections of GSK-3 inhibitor (AR-A014418), *: p < 0.05 vs. C.

Fig 3: Inhibition of p38 MAPK partially protects against LCM-mediated loss of myotube diameter. (A) Myotube diameter analysis of Control Media + Vehicle, Control Media + SB202190, LCM + Vehicle, and LCM + SB202190. (B) MAPKAPK-2 phosphorylation relative to total protein content following 18 h of treatments. (C) Puromycin incorporated for groups Control Media + Vehicle, Control Media + SB202190, LCM + Vehicle, and LCM + SB202190 after 30 min puromycin treatment following 18 h of treatments. (D) Protein content of ubiquitin following 18 h of Control Media + Vehicle, Control Media + SB202190, LCM + Vehicle, or LCM + SB202190 treatment. (E) Protein content of p-4EBP1 relative to total 4EBP1, Deptor, p-FOXO3 relative to total FOXO3, and p-FOXO1 content relative to total FOXO1 following 18 h of Control Media + Vehicle, Control Media + SB202190, LCM + Vehicle, or LCM + SB202190 treatment. (F) Atrogin-1 and MuRF-1 mRNA content following 18 h of Control Media + Vehicle, Control Media + SB202190, LCM + Vehicle, or LCM + SB202190 treatment. All measured in C2C12 myotubes and normalized to and Ponceau S. Data are mean ± SEM. (G) Representative micrographs and immunoblot images for each protein of interest taken in order from same membrane. N of 6 was utilized for each group. Lettering denotes statistical significance (means that do not share the same letter are statistically different) at an alpha set at P < 0.05. ME indicates statistical Main Effect of indicated factor(s).

Fig 4: Suppression of cellular translation is attributable to HIV-1-dependent dephosphorylation of eIF4E and 4E-BP1.(A) HEK 293 cells were transfected with HIV-1NL4-3 or ?VifVprX (?VV) for 24 or 48 hour, as indicated. Equivalent whole-cell extracts were immunoblotted with antiserum against phospho-eIF2a Ser51, total eIF2a, phospho-eIF4E Ser209 or total eIF4E, respectively. (B) CEMx174 cells were infected with HIV-1 or ?VifVprX (?VV) and evaluated at 12 hour intervals. Equivalent whole-cell extracts were immunoblotted with the indicated antiserum.

Fig 5: PR20 neither influences the activation of TORC or AMPK nor ER stress. Mixed spinal cord cultures were exposed to PR20 for 48 h and then processed for immunoblotting. A, Representative immunoblot images of biochemical markers of TORC activation (e.g., phospho-4EBP1 and phospho-S6K), AMPK activation, or activation of the ER stress response (KDEL) shows no difference between PR20 versus vehicle-treated cells. B, Quantification of the bands with intensity values from samples were averaged and normalized to actin loading controls. Dark grey bars correspond to the presence of PR20, and light grey bars correspond to levels without PR20. Error bars represent SE.